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Finding the Fourth Proportional to 86.87, 119.77 and 84.04

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Solution

The fourth proportional to 86.87, 119.77 and 84.04 is: 115.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.87 : 119.77 = 84.04 : x
  2. Step 2: Convert to fraction form
    86.87/119.77 = 84.04/x
  3. Step 3: Cross multiply
    86.87x = 119.77 × 84.04
  4. Step 4: Simplify right side
    86.87x = 10,064.96
  5. Step 5: Solve for x
    x = 10,064.96/86.87
  6. Step 6: Final answer
    x = 115.86

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.